Manufacture of paper and the like.



an FJIGE.

CHARLES IVILLIAIVI FISH. OF RAWCLIF FE, NEAR GOOLE, ENGLAND, ASSIGNOR TO THE AMBER SIZE & CHEMICAL COMPANY. LIMITED, OF LONDON, ENGLAND.

MANUFACTURE OF PAPER AND'THE LIKE.

No Drawing.

To all whom it may concern Be it known that I. Crmnnns \VILLIAM FisH, a subject of the King of Great Britain and Ireland, and residing at Reedholme,

' Rawclifie, near Goole, in the county of York,

England, have invented certain new and useful Improvements in the Manufacture of Paper and the like, of which the following is a specification.

This invention relates to a new or improved process of sizing pulp in the manufacture of paper and the like.

In the process ordinarily employed a size is added consisting of a resinate of soda. This requires to be fixed, that is, decomposed into its components, resin and soda, so that the resin shall be freed from the soda in a finely divided state, one of the soluble aluminium salts. such as aluminium sulfate, alum. or alumino ferric cake (sulfate of iron and alumina) being added for this purpose.

' It has befere-been proposed to substitute the aluminiumsalts wholly by an acid bisulfate or by mixtures of aluminium sulfate and a bisulfate, but Ihave found by experiment that complete substitution does not give useful results, and that mixtures of aluminium salts with bisulfate of soda as previously proposed are also objectionable, as difficulties arise from the two components being added to the pulp at the same time.

, Now the object of the present invention is to substitute to a great extent for the aluminium salts, niter cake or crude-bisulfate of soda which is almost a waste product in the manufacture of nitric acid, hydrochloric acid and some other chemicals, so that the quantity of niter cake or crude bisulfate may be considerably in excess of the aluminium salts.

After a large amount of experimenting on a manufacturing scale it has been found that the total substitution of alum by niter cake was only practicable when making common grade papers When the 'nitercake and the resinate of soda were alone employed, the troubles hereafter mentioned were largely encountered, whereas these troubles are overcome or no longer exist in the improved process now describe. y

It is as follows: The size isadded to the pulp in the beating engine thoroughly mixed, then a small percentage of alum, say

Specification of Letters Patent. i I PgmbgntlgdlJune 12, 1191?, Application filed. December 28,1916. Serial No. 139,403.

half per cent. to one per cent. of the pulp, is added, varying in amount according to the hardness of the water used, and also to the degrees of sizing required in the paper and the class of material employed. After this has becomejthoroughly distributed in the pulp the niter cake is added, the weight of niter cake used being usually about the same for each class of material as the amount of alum ordinarily employed, less perhaps the small amount already added. The quantity of alum, however, required varies greatly with different classes of paper, but this is well known to the trade and therefore the amount of niter cake can be very easily determined.

I find practically that one part of niter cake containing 75 per cent. bisulfate of soda replaces one part of alum.

One thing, however, is essential: the niter cake must be added last.v If this is not done or particles of pulp to stick to them, and p in the case of M. G. single cylinder machines, commonly known as Yankee, "the finish is seriously interfered with owing to resinbeing, conveyed fromthe paper on to r the cylinder producing unglazed patches and blotchesor specks of resin on the paper.

Not only is the paper harder when sized by my process but the coloring matter, especially artificial organic colors and dye 'stufi's whether basic acid or salt and even the mineral colors, suchas oche'r and the like, and other inorganic pigments such as chrome yellow, Prussian blue. paste and the like, are well fixed in and on the fiber, thus insuring good shades being obtained.

By my process also very considerable economy of cost is obtained over'any other sizing process I am acquainted with.

As illustrations of my process I give the following casesof actual manufacture which have been very successful.

12 cwts. of strong unbleached air-dried sulfite pulp is filled into the beater and at the. same time 7 lbs. of alum and 40 lbs. of size,'.containing 30 percent. to 35 per cent.

of resinate of soda, are added After these have become thoroughly mixed With the pulp 5 I D. C. 30 to 40 lbs., 7 lbs. of alumino ferric is first added when filling into the beater with the usual quantity of water 11 cwts.-

of a mixture consisting of 65 per cent. of mechanical Wood pulp and 35 per cent. strongunbleached sulfite pulp reckoned dry,

" then 100 lbs. of size 32 per cent. strength is added and after that 40 lbs, of niter cake (containing 87 per cent. bisulfate of soda, 9 per cent. sulfate of soda and 4 percent.

' water).

These two illustrations Will-show the general Working of my invention but in every different variety of pulp and for nearly every different use the quantities differ to some extent. a

The

aim features of my invention are:- (1) the addition of a very small percentage of alum, and (2) the thorough mixture and solution in the furnish before the niter cake is added. I find that to secure successful results it .isnecessary to add the niter cake after the size and alumina salts have been'introduped .into the. pulp.

Havlng now particularly described and ascertained the nature of my said invention and in What manner the same is to be perforn1ed, I declare that What I claim is 1. In the process of sizing pulp for the manufacture of paper or the like using niter' cake and alumina salts for fixing the size, the addition of the niter cake separatefrom the alumina salts and only after the size and the alumina saltslnu'ebeen incorporated .in thepulp, substantially as described.

f 2. In the process of'sizing pulp-for the manufacture of paper and the like, thorou hl mixin the re uisite k-uanti'tv .of n y r;

resin size with the pulp and adding a small quantity of a soluble alumina'salt, say half percent-.to one per cent. of the stuff in the heater, and When these are thoroughly mixed adding bisulfate of soda or niter cake, sul'lstantially as described.

In testimony. whereof, I have aflixed my signature.

CHARLES VVILLL-XM FISH. 

